My current home network is still far away from what I would consider an ideal setup. Besides the main router, I also have a WiFi extender that creates a separate network. From time to time I change the router location, and many of my wirelessly connected devices require special attention often because I forget to update the credentials to the closest network before the move. Not this time.

In my home, I have a mechanical ventilation system with heat recovery powered by Stiebel Eltron V-400. Basically, it’s a large fan with air inflows and outflows ducts. Besides some built-in automation, it’s a pretty dumb device. Without a dedicated gateway (which costs extra money), I can only control it or see its current parameters on the controller, either on the unit or in the hall.

I thought it would be nice to collect some data from this device, both for some kind of analysis and out of curiosity. I run Home Assistant, which can display dedicated graphs and dashboards for such purpose. And, because I recently played with ESP boards, the idea was born pretty quickly.